<s>
An	O
irregular	B-Algorithm
matrix	I-Algorithm
,	O
or	O
ragged	B-Algorithm
matrix	I-Algorithm
,	O
is	O
a	O
matrix	B-Architecture
that	O
has	O
a	O
different	O
number	O
of	O
elements	O
in	O
each	O
row	O
.	O
</s>
<s>
Ragged	O
matrices	O
are	O
not	O
used	O
in	O
linear	B-Language
algebra	I-Language
,	O
since	O
standard	O
matrix	B-Architecture
transformations	O
cannot	O
be	O
performed	O
on	O
them	O
,	O
but	O
they	O
are	O
useful	O
as	O
arrays	O
in	O
computing	O
.	O
</s>
<s>
Irregular	O
matrices	O
are	O
typically	O
stored	O
using	O
Iliffe	B-Data_Structure
vectors	I-Data_Structure
.	O
</s>
<s>
For	O
example	O
,	O
the	O
following	O
is	O
an	O
irregular	B-Algorithm
matrix	I-Algorithm
:	O
</s>
